
import java.util.*;
public class GiaiPhuongTrinh {
//Giai phuong trinh bac 2
	//demo comment
	public void GiaiPhuongTrinh()
	{
		 double a,b,c,x1,x2;
		 
	     double delta;
	 
	     Scanner input = new Scanner(System.in);
	 
	     System.out.print("Nhap a= ");
	 
	     a=input.nextFloat();
	 
	     System.out.print("Nhap b= ");
	 
	     b=input.nextFloat();
	 
	     System.out.print("Nhap c= ");
	 
	     c=input.nextFloat();
	 
	       if(a==0){
	 
	         if(b==0){
	 
	           if(c==0){
	 
	             System.out.println("Phuong trinh vo so nghiem ");
	 
	           }
	 
	           else{
	 
	             System.out.println("Phuong trinh vo nghiem ");
	 
	           }
	 
	         }
	 
	         else{
	 
	           x1=(-c)/b;
	 
	           System.out.println("Phuong trinh co nghiem duy nhat : " + x1);
	 
	         }
	 
	       }
	 
	       else{
	 
	         delta= (b*b)-(4*a*c);
	 
	         if(delta<0){
	 
	           System.out.println("Phuong trinh vo nghiem");
	 
	         }
	 
	         if(delta==0){
	 
	           x1= -b/(2*a);
	 
	           System.out.println("Phuong trinh co nghiem duy nhat" +x1);
	 
	         }
	 
	         if(delta>0){
	 
	           x1=(-b+Math.sqrt(delta))/(2*a);
	 
	           x2=(-b-Math.sqrt(delta))/(2*a);
	 
	           System.out.println("Phuong trinh co 2 nghiem" );
	 
	           System.out.println(x1);
	 
	           System.out.println(x2);
	 
	         }
	 
	       }
	 
	}

		/**
		 * @param args
		 */
		public static void main(String[] args) {
			// TODO Auto-generated method stub
			GiaiPhuongTrinh a = new GiaiPhuongTrinh();
			
			a.GiaiPhuongTrinh();
		}

	}
